1. Field of the Invention
The present invention relates to high voltage transmission line fittings or hardware commonly found in electric utility systems. These fittings are manufactured by casting or forging and may be composed of ferrous or other suitable alloys.
2. State of the Prior Art
The invention specifically deals with a fitting called an eyelet which finds many uses in high voltage transmission lines. Conductors, cables and insulators and other components must be supported or attached to or at terminations and this fitting finds extensive use in this application. Typically, one side of the eyelet has a base with an elongated hole for a bolt whose diameter is generally on the order of 5/8" or 3/4". This elongated hole may cause eccentric loading of the eyelet and, therefore, its ultimate structural strength is reduced. As an example, pull tests on standard fittings show strength reduction of about 10% when tested with maximum eccentricity. As a result, additional material must be provided, in accordance with the engineering design of such eyelets, to insure adequate strength, a clear waste of material if the strength could be otherwise attained. Also, the elongated hole occasionally does not restrain the bolt head in a location that would rotationally lock the bolt head. This problem is especially common with the hexagonally shaped bolt head. As a result two tools are necessary to tighten the bolt and nut assembly when this condition occurs. The elongated hole is also disadvantageous in requiring extensive manufacturing operations such as core setting or punching.